I have applied the technique to implement a written language
identification program. At the moment, the system knows about 69
natural languages (counting Esperanto as a natural language).

The textcat programme is not any langer actively maintained by me. However, the
SpamAssassin spam filter programme includes a version of TextCat. They have
been working on it some more, so perhaps you want to get their version from http://spamassassin.apache.org.

Remotely related links

LIFI:
Language Identification From Images. Quote: The Language
Identification From Images project (LIFI) is concerned with the
automated identification of the script (alphabet) used in a document
image. Our initial phase, from 1994 to 1995, focused on
machine-printed documents. The second phase, from 1997 to 1998,
focused on handwritten documents. We will soon begin a new project
concerning how to use our script identification techniques to segment
multi-script document images.